The present application discloses a dock leveler, and particularly a dock leveler including a widened deck member carrying integral dock bumpers.
Dock levelers are widely used to facilitate the loading and unloading of vehicles at a loading dock. The dock leveler forms a bridge between the building, such as a warehouse or distribution facility, and the back end of the vehicle being loaded or unloaded. A gap typically exists between the building exterior wall and the rear end of the vehicle by virtue of the fact that the vehicle engages against bumpers on the exterior wall. The bumpers are disposed on the wall to protect both the vehicle and the wall against the damage that would result from the vehicle directly engaging the wall. A set of bumpers B, disposed on either side of a dock leveler D, are shown in the prior art FIG. 1. To bridge the gap thus formed, a dock leveler typically employs a deck member, labeled M in FIG. 1, that is hingedly connected about its rear end at H to a support structure disposed within a pit P. Hingedly connected to the front end of the deck D is a lip L which is movable between a downwardly hanging, stored or xe2x80x9cpendantxe2x80x9d position and the extended position shown in FIG. 1. In the extended position, the lip would be placed in the rear of the vehicle being loaded or unloaded to bridge the gap from the vehicle into the building, and to facilitate loading and unloading. The hinged connection H of the deck to the supporting structure allows the entire leveler to move up and down with the vehicle as it is loaded and unloaded. As a vehicle is unloaded its suspension will tend to raise the floor of the vehicle, and thus the leveler itself. Similarly, as a vehicle is loaded the weight of the cargo will tend to depress the floor of the vehicle against the suspension. Dock levelers are also vertically adjustable in this manner as vehicles are disposed at a wide variety of heights relative to the roadway.
In a typical installation, a pit is formed for receiving the dock leveler. The pit is indicated generally in FIG. 1 by the reference letter P. The pit provides space for the leveler itself, as well as for the actuation mechanism for raising and moving the leveler into its operating positions, and returning it to a stored position. The dock bumpers B are typically disposed on the vertical exterior building wall just laterally of the pit sidewalls. Under certain conditions, this arrangement can be problematic. In FIG. 1, the dock leveler is shown in a so-called below dock position. That is, the deck is disposed at a declined angle with respect to the floor F surrounding the pit P. As can be seen from FIG. 1, the front wall W of the building and the side wall S of the pit P thus form ledges at the front and side edges of the deck, respectively. Certain vehicles to be loaded or unloaded with the leveler may be wider than the width of the dock leveler. In such a situation, the presence of the ledges when the deck is in a below dock position may be a significant impediment to unloading the vehicle. For example, if a load were being removed from a vehicle with a fork truck disposed on the leveler in FIG. 1, and if that load had a width such that a portion of it extended beyond the lateral edge of the lip L and if, for example, there were insufficient headroom inside the vehicle preventing the load from being elevated, that cargo could strike the front wall W of the loading dock or the bumper B, leading to damage of the cargo and/or impeding the efficiency of the unloading process. For this reason, facilities that service a large number of wide vehicles (i.e., vehicles wider than the width of standard dock levelers) often employ truck levelers. Truck levelers are lifts that can lift the vehicle to a raised position relative to the loading dock, so that the vehicle can be serviced by a dock leveler without the need for the dock leveler to assume a below dock position as in FIG. 1, thus avoiding interference between the cargo and the dock wall W or bumper B. The problem of the front wall of the building and the side wall of the dock leveler pit forming a barrier to free and easy movement of cargo being loaded and unloaded could also be solved simply by having a dock leveler of a wider width. However, if a standard dock leveler were as wide a the vehicle itself, there would not be dock wall available for the purpose of mounting bumpers. Thus, there would be the risk that the vehicle would back directly into the leveler, damaging both the leveler and the vehicle itself including impeding the functionality of the dock leveler.
There is thus provided a dock leveler preferably of increased width, and which includes integrally-mounted bumpers. In a preferred embodiment, the deck of the dock leveler is wider than the lip, with the leveler extending laterally beyond the width of the lip on each side. Mounted to the front end of the deck, and disposed laterally to the lip, are the integral bumpers. These bumpers extend from the front end of the deck to a significant projection in front of the lip to ensure that the parking vehicle cannot back into the lip as it approaches the dock. A spacer member may preferably be included in the bumper assembly. Such a spacer is disposed adjacent the front end of the deck. The remainder of the bumper assembly is then mounted to the spacer member. The spacer insures that the bumper is disposed in front of the lip when the lip is in a pendant position to maintain a gap between the rear of the vehicle and the pendant lip. The spacer member may preferably include an access hole to allow insertion and removal of the hinge pin which hinges the lip to the deck. Alternatively, the spacer may be provided with an access notch for the hinge pin. Since the bumpers integrally carried on the dock will now be subject to the impact of the backing truck, which impact would conventionally be dispersed into the building wall, the dock leveler disclosed herein preferably includes a bumper support structure to absorb and distribute the additional forces exerted on the dock leveler by the vehicle contacting the integral bumpers. In a representative embodiment, the support structure includes a structural member disposed between a rear portion of the deck and the upstanding rear wall of the dock leveler pit.
The dock leveler with integral bumpers disclosed herein assists in solving the problems typically associated with loading and unloading vehicles having a width greater than the width of the dock leveler, particularly in below dock situations. At the same time, it provides a solution that is economical, simple of construction that does not require a significant number of moving parts, and can provide a larger, unimpeded maneuvering surface for enhancing lift truck operation and safety.